CDMA (Code Division Multiple Access is Code-division multiple access)

Capability transfer large volumes of information it was put by developers of the American company Qualcom "by default", unlike the GSM standard where data transmission is so-called "superstructure" in a telephone system.

Over 250 operators in 99 countries of the world use CDMA technologies with the different frequency ranges (450/800/900/2000 MHz). The number of subscribers of CDMA EV-DO networks approaches 100 million.

In Russia the CDMA technology develops with the frequency range of 450 MHz as it is recognized as the most suitable standard for step-by-step "digitalization" of NMT-450i networks.

CDMA 450 MHz (IMT-MC-450) is the technology complex of new generation uniting the highest transmission quality of the speech and exclusively high data transfer rates.

Advantages of the CDMA standard 450 MHz

• Pure sounding of the speech
• Lack of extraneous noises and high confidentiality level of a talk — initially the standard was developed for the U.S. Armed Forces. Decrypt a signal without knowledge of the code impracticablly.
• The increased capacity of network providing implementation of unlimited accesses both in voice traffic, and in a data transmission traffic
• There is no strict number of channels. With increase in loading losses in data transmission packets increase, but at the same time there is no break of connections.
• The high data transfer rate allowing to implement a full-fledged work on the Internet and to use all opportunities of business solutions of the class "remote office" as using the mobile phone, and having connected it to the computer.
• Much higher level of security of cell phones in comparison with devices of other standards (peak capacity of the modern GSM phones is about 1.0 W while this indicator of CDMA phones does not exceed 0.2 W that, including, well affects also work duration without recharge).

FH-CDMA

Code-division multiple access of channels (with a jump on frequency). Abbreviation of Frequency Hopping Code Division Multiple Access. The main advantages of FH-CDMA technology — high noise immunity and small sensitivity to dispersion of capacities of subscriber devices.